MAX1450 Datasheet, PDF (3/12 Pages) Maxim Integrated Products – Low-Cost, 1%-Accurate Signal Conditioner for Piezoresistive Sensors

Low-Cost, 1%-Accurate Signal Conditioner
for Piezoresistive Sensors
ELECTRICAL CHARACTERISTICS (continued)
(V_DD = +5V, V_SS = 0, T_A = T_MIN to T_MAX, unless otherwise noted. Typical values are at T_A = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX UNITS
CURRENT SOURCE
Bridge Current Range
I_BDRIVE
0.1
0.5
2.0
mA
Bridge Voltage Swing
V_BDRIVE
V_{SS +}
1.3
V_{DD -}
1.3
V
Current-Source Gain
AA
∆I_BDRIVE/∆I_ISRC (Figure 2)
13
µA/µA
Current-Source Input Voltage
Range
BUFFER (BBUF)
Voltage Swing
Current Drive
V_ISRC
No load
V_BDRIVE = 2.5V
V_{SS +}
1.3
V_{SS +}
1.3
-100
V_DD-
1.3
V
V_{DD -}
1.3
V
100
µA
Offset Voltage
V_OFS (V_BDRIVE - V_BBUF) at V_BDRIVE = 2.5V, no load
-20
20
mV
Note 1: Contact factory for high-volume applications requiring less than 1.5mA.
Note 2: All electronics temperature errors are compensated together with the sensor errors.
Note 3: The sensor and the MAX1450 must always be at the same temperature during calibration and use.
Note 4: This is the maximum allowable sensor offset at minimum gain (39V/V).
Note 5: This is the sensor’s sensitivity normalized to its drive voltage, assuming a desired full-span output (FSO) of 4V and a bridge
voltage of 2.5V. Operating at lower bridge excitation voltages can accommodate higher sensitivities.
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